in Sri Lanka - Ministry of Environment

ThreatsVast majority of pteridophyte flora and almost all endemic pteridophytes in Sri Lanka areconfined to the wet zone areas of the lowland, sub montane and montane regions. However,most of the remaining forests in the wet zone area are fragmented and small. They arecontinued to be degraded due to illegal encroachment and suffer further fragmentation due tohigher population densities in such areas. The area is highly subjected to habitat loss, spreadof alien-invasive species, soil erosion and environmental pollution. These are consideredas the most immediate threats to the pteridophyte flora of Sri Lanka. In areas such as theKnuckles region, the forest understorey which is the main habitat for pteridophytes has beencleared for cardamom cultivation whereas in Udawattakele forest understorey is invaded byalien-invasive species; also make significant threats to regeneration of pteridophytes. Anotherthreat of increasing importance is the illicit removal and over exploitation of ornamentallyimportant rare ferns from the wild. These problems will be worsening by change of climateand increasing human population pressure.Conservation issuesThe effective conservation of Sri Lankan pteridophyte flora will depend largely on how effectivethe conservation of natural forests in the wet zone areas of the country. For this, minimizing offragmentation and habitat loss through effective land use planning and a sound policy frameworkis a must. Further, according to the present Red Listing, of the 335 pteridophyte species,219 species (66%) are listed as threatened species (20, 41, 87 and 71 species are criticallyendangered and possibly extinct (CR(PE)) critically endangered (CR), endangered (EN) andvulnerable (VU). Another 40 species are listed as near threatened (NT). This highlighted that, inaddition to conservation of natural forests in the wet zone areas, monitoring of populations of atleast threatened species is a necessary to understand effectiveness of the in situ conservation ofpteridophyte flora. At present, ex situ conservation is limited to a few local species at the RoyalBotanic Gardens, Peradeniya and Botanic Gardens of Hakgala and Henerathgoda. Therefore,strengthening of ferneries of the network of the National Botanic Gardens is urgently required asa supplementary conservation measure for Sri Lankan pteridophytes.Research gaps and needsFurther enhancement of current knowledge and understanding of pteridophytes flora needsseveral measures. As highlighted a comprehensive taxonomic revision need to be carried outin the light of recent floral survey in the South Asia and recent advances of taxonomy due touse of molecular investigations. A close collaboration between pteridologists in India (as wellas elsewhere) and Sri Lanka is a pre-requisite. Much of the specimens of pteridophytes havebeen collected from 1847 to 1900 by European pteridologists and deposited in herbaria ofelsewhere than the National Herbarium. Thus, an island-wide floristic survey on pteridophytetaxa is urgently required in Sri Lanka which helps to revise the taxonomy, distribution andother conservation issues of the island pteridophyte flora. Upgrading of the collection of theNational Herbarium is also a must and should be carried out parallel to the floristic survey.Further, recent work by Ranil et al., (2008b) provides encouraging results on domesticationof C. walkerae and need to expand to other species which has commercial potentials. Publicawareness programs on the conservation and sustainable use of pteridophytes should also beinitiated promoting in situ and ex situ conservation.151